OBJECTIVE: The objective of this project is to produce an historical monograph surveying the principal controversies that have attended child immunization in the United States over the past half-century. Within this framework it will describe the evolution of vaccine policy, with the intent of illuminating its effectiveness and consequences. It will relate how health professionals have engaged with other social groups (public health organizations, government agencies, the courts, media, and anti-vaccine groups) to define and construct American vaccine policy. SIGNIFICANCE: Current childhood immunization policy has evolved over the past 50 years in an often fragmented and reactive manner. An understanding of its history, beginning with the first national immunization drives following polio vaccine through the litigation crises surrounding pertussis vaccine, is essential to the re-formulation of a more coherent and unified national policy. Although enormous strides have been made in immunization delivery over the past twenty-five years, two other developments threaten to undermine this progress. The rise of anti-vaccine sentiment, fueled by the media and expressed through litigation, has become an important political force that remains poorly understood by the medical profession. Corporations also have been withdrawing from vaccine research, threatening higher prices and supply shortages. This project will seek to show how efforts to promote vaccine delivery, development, and safety can affect and even undermine one another. METHODS: The historical research involved in this project will include primary source material in the published literature as well as select archives. Its time frame will be bounded by 1956 (the release of the Salk vaccine) and the Childhood Immunization Act of 1993. The text will focus on the issues raised by three vaccines (DTP, measles, and pertussis)and the public issues and controversies generated by each. Sources will include professional medical literature, legal cases, popular media, and extensive government documents related to congressional hearings and policy.